Crimson Moth
Source: Pet Battle. Prefers to dwell in humid, tropical areas and feed on Kingsblood nectar. Flying type. Flew all over Northern Stranglethorn and the Cape zones looking for this moth to tame and didn't see it.
The Crimson Moth is a wild pet found in Northern Stranglethorn and the Cape of Stranglethorn, most reliably encountered as a secondary pet in wild battles rather than as a standalone primary.
Guide awaiting review
Travel to Northern Stranglethorn
Head to Northern Stranglethorn. While Crimson Moths can be seen flying visually throughout the zone, they are difficult to find as standalone battlable pets.
Trigger wild pet battles
Engage Strand Crabs and other wild pets in battle — the Crimson Moth has been found appearing as a secondary pet joining the fight, which is the most consistent way to encounter a capturable one.
Capture the secondary Crimson Moth
When a Crimson Moth appears as a secondary pet in a battle, use a Trap ability to capture it. After a successful capture, it will appear normally in your Pet Journal.
Tips
Crimson Moths have also been spotted as primary capturable pets around the Kal'ai Ruins in Northern Stranglethorn.